9.1.c
#include <stdio.h>
double min(double, double);
int main(void) {
double x, y;
printf("Enter two numbers (q to quit): ");
while (scanf("%lf %lf", &x, &y) == 2) {
printf("The smaller number is %f.\n", min(x,y));
printf("Next two values (q to quit): ");
}
printf(...